She completed treatment for emotional and physical issues in January 2011 and has spoken about cutting herself and about her bipolar disorder.

So the news of Cory Monteith's death hit her particularly hard.

"All it takes is one moment of vulnerability to get slipped into your addiction," she told People Wednesday. "He didn't choose to die. It was the disease. It can creep up on you at any moment. It only takes one moment of relapse to potentially die. It's really scary, but I'm really hoping that from this, people are able to see this is a very, very, very dangerous disease."

"They can turn 21 and have their turn-21st-birthday," she says. "I don't think that I – I just don't put myself in those situations where I'm going to be at those 21st birthdays. I don't go to clubs. I just know it's something I can't do without being triggered. And that's okay."